This invention relates to a process for recovering lube oil base stocks from used motor oil formulations, asphalt blend compositions containing Used Motor Oil (UMO) bottoms from the process, and asphalt pavement compositions containing the asphalt blend compositions.
Automotive lubricating oils are usually formulated from paraffin based petroleum distillate oils or from synthetic base lubricating oils. Lubricating oils are combined with additives such as soaps, extreme pressure (E.P.) agents, viscosity index (V.I.) improvers, antifoamants, rust inhibitors, antiwear agents, antioxidants, and polymeric dispersants to produce an engine lubricating oil of SAE 5 to SAE 60 viscosity.
After use, this oil is collected from truck and bus fleets, automobile service stations, and municipal recycling centers for reclaiming. This collected oil contains organo-metallic additives such as zinc dialkylthiophosphate from the original lubricating oil formulation, sludge formed in the engine, and water. The used oil may also contain contaminants such as waste grease, brake fluid, transmission oil, transformer oil, railroad lubricant, crude oil, antifreeze, dry cleaning fluid, degreasing solvents such as trichloroethylene, edible fats and oils, mineral acids, soot, earth and waste of unknown origin.
Our process, disclosed in U.S. Ser. No. 09/026,367, disclosed a new process for reprocessing UMO. This invention is directed to asphalt blends and asphalt pavements comprising the residue from our UMO process.